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Diffusion and Leaching of Selected Radionuclides (Iodine-129, Technetium-99, and Uranium) Through Category 3 Waste Encasement Concrete and Soil Fill Material

Description: An assessment of long-term performance of Category 3 waste-enclosing cement grouts requires data about the leachability/diffusion of radionuclide species (iodine-129, technetium-99, and uranium) when the waste forms come in contact with groundwater. Leachability data were collected by conducting dynamic (ANS-16.1) and static leach tests on radionuclide-containing cement specimens. The diffusivity of radionuclides in soil and concrete media was collected by conducting soil-soil and concrete-soil half-cell experiments.
Date: September 24, 2001
Creator: Mattigod, Shas V.; Whyatt, Greg A.; Serne, R. Jeffrey; Martin, P. F.; Schwab, Kristen E. & Wood, Marcus I.
Partner: UNT Libraries Government Documents Department

Innovations in Copper Leaching Employing Ferric Sulphate-Sulphuric Acid

Description: From Introduction: "The Bureau of Mines has attempted to develop a cheap and efficient solvent that would especially meet the requirements of smaller plants. (See Bibliography). A method of producing this solution from sulphurous products and waste liquors was developed by the bureau and tried successfully on a test-plant scale at the Southwest Experiment Station in cooperation with the department of mining and metallurgy, University of Arizona, Tuscon, Ariz."
Date: 1930
Creator: Keyes, Harmon E.
Partner: UNT Libraries Government Documents Department

Copper Leaching Practices in the Western United States

Description: Report issued by the U.S. Bureau of Mines discussing copper leaching in the Western United States. As stated in the introduction, "the purpose of this report is to describe and discuss the different leaching and recovery methods currently employed in the production of copper from low-grade ores in the Western states" (p. 1). This report includes tables, illustrations, and photographs.
Date: 1968
Creator: Sheffer, Herman W. & Evans, LaMar G.
Partner: UNT Libraries Government Documents Department

Characterization of Dried and Torrefied Arundo Donax Biomass for Inorganic Species Prior to Combustion

Description: Portland General Electric (PGE) potentially plans to replace the coal with torrefied Arundo donax for their Boardman coal-fired power plant by 2020. Since there is only a limited amount of experience with this high yield energy crop, PGE would like to characterize raw and torrefied Arundo before a test burn and therefore avoid possible ash related operational problems such as slagging, deposit formation and corrosion. This report describes the results from characterization of ground and cross-sectioned samples of Arundo with a high-resolution scanning electron microscopy and energy dispersive spectroscopy, and also includes analytical results from a short water-leaching test for concentrations of Ca, Mg, K, Na, S, and Cl in the non-leached and leached Arundo and leachates. SEM-EDS analysis of torrefied Arundo revealed that condensation of volatile components during torrefaction can result in their undesirable re-deposition on the outside surfaces in the form of amorphous or crystallized clusters with a size from a few µm’s to as large as 100 µm. A short exposure of Arundo to water resulted in an efficient removal of volatile species from the raw and torrefied Arundo, e.g., ~ 98 wt% of total K and Cl, and ~75 wt% of total S were removed from raw Arundo, and more than 90 wt% of total K and Cl, and 70 wt% of S from torrefied Arundo, suggesting that water-leaching of Arundo before combustion can be an effective pre-treatment method because high concentrations of Cl increase emissions of HCl, and in combination with K can form large amounts of KCl deposits on boiler surfaces and in combination with H2O or SO3 cause corrosion.
Date: August 1, 2012
Creator: Matyas, Josef; Johnson, Bradley R. & Cabe, James E.
Partner: UNT Libraries Government Documents Department

Evaluation of Potential Hydrocarbon Transport at the UC-4 Emplacement Hole, Central Nevada Test Area

Description: Emplacement hole UC-4 was drilled in 1969 at the Central Nevada Test Area and left filled with drilling mud. Surface characterization samples collected from abandoned mud pits in the area yielded elevated concentrations of total petroleum hydrocarbon, thereby raising a concern that the mud-filled emplacement hole may be leaching hydrocarbons into alluvial aquifers. This study was initiated to address this concern. An analytical solution for flow near a wellbore was used to calculate the amount of time it would take for a contaminant to move through the mud-filled well and into the surrounding aquifer. No hydraulic data are available from the emplacement hole; therefore, ranges of hydraulic conductivity and porosity were used in 100 Monte Carlo realizations to estimate a median travel time. Laboratory experiments were performed on samples collected from the central mud pit to determine the hydrocarbon release function for the bentonite drilling mud. The median contaminant breakthrough took about 12,000 years to travel 10 m, while the initial breakthrough took about 300 years and the final breakthrough took about 33,000 years. At a distance of about 10 m away from the emplacement hole, transport velocity is dominated by the hydraulics of the aquifer and not by the emplacement hole hydraulics. It would take an additional 45,500 years for the contaminant to travel 800 m to the U.S. Department of Energy land exclusion boundary. Travel times were primarily affected by the hydraulic conductivity and porosity of the drilling mud, then by the hydraulic conductivity, porosity and hydraulic gradient of the alluvial aquifer, followed by the hydrocarbon release function.
Date: September 30, 1998
Creator: Lyles, Brad F.; Papelis, Charalambos; Pohll, Greg & Sloop, Derek
Partner: UNT Libraries Government Documents Department

Toxic Characteristic Leaching Procedure (TCLP) Testing of Waste Glass and K-3 Refractory

Description: The U. S. Environmental Protection Agency (EPA) issued revised Resource Conservation and Recovery Act (RCRA) Phase IV Land Disposal Restrictions (LDR's) on May 26 1998. The new regulation requires that any waste characteristically hazardous for the metals As, Ba, Cd, Cr, Pb, Hg, Se, and Ag will have to be treated to meet the LDR Universal Treatment Standards (UTS) for each metal prior to land disposal. Since EPA regulations continue to become more stringent, here-to-fore unpublished TCLP data generated during testing of simulated High Level Waste (HLW) glass, including the Evnironmental Assessment glass and K-3 melter refractory, will be reviewed. The refractory TCLP data compilation includes K-3 refractory in contact with DWPF simulated glass in a pilot scale melter and K-3 refractory in contact with actual mixed waste glass in a 5 ton a day GTS Duratek melter.
Date: April 23, 1999
Creator: Jantzen, C.M.
Partner: UNT Libraries Government Documents Department

Leaching Nonsulphide Copper Ores with Sulphur Dioxide

Description: Report issued by the Bureau of Mines discussing the sulfurous acid leaching of the Southwest experiment station. Operations and analyses of the experiment station are presented. This report includes tables, illustrations, and photographs.
Date: May 1923
Creator: Van Barneveld, Charles E. & Leaver, Edmund S.
Partner: UNT Libraries Government Documents Department

Two Stage Leaching Tests on Utex Ore

Description: Introduction: The object of this test work was to determine the practicability of a two-stage leach using ion-exchange as the method of uranium concentration.
Date: July 22, 1954
Creator: Stanley, Alan; Eisenhauer, Robert & Richardson, Stanley
Partner: UNT Libraries Government Documents Department

Factors Governing the Entry of Solutions into Ores During Leaching

Description: Technical paper issued by the Bureau of Mines over studies on the leaching of copper-bearing ores. As stated in the introduction, the "penetration of the leaching medium into the body of the ore particles" (p. 1) is discussed. This paper includes tables, photographs, and illustrations.
Date: 1929
Creator: Sullivan, John D.; Keck, Walter E. & Oldright, George L.
Partner: UNT Libraries Government Documents Department

Analysis of cavern stability at the Bryan Mound SPR site.

Description: This report presents computational analyses that simulate the structural response of caverns at the Strategic Petroleum Reserve Bryan Mound site. The cavern field comprises 20 caverns. Five caverns (1, 2, 4, and 5; 3 was later plugged and abandoned) were acquired from industry and have unusual shapes and a history dating back to 1946. The other 16 caverns (101-116) were leached according to SPR standards in the mid-1980s and have tall cylindrical shapes. The history of the caverns and their shapes are simulated in a 3-D geomechanics model of the site that predicts deformations, strains, and stresses. Future leaching scenarios due to oil drawdowns using fresh water are also simulated by increasing the volume of the caverns. Cavern pressures are varied in the model to capture operational practices in the field. The results of the finite element model are interpreted to provide information on the current and future status of subsidence, well integrity, and cavern stability. The most significant result in this report is relevant to caverns 1, 2, and 5. The caverns have non-cylindrical shapes and have potential regions where the surrounding salt may be damaged during workover procedures. During a workover the normal cavern operating pressure is lowered to service a well. At this point the wellhead pressures are atmospheric. When the workover is complete, the cavern is repressurized. The resulting elastic stresses are sufficient to cause tension and large deviatoric stresses at several locations. With time, these stresses relax to a compressive state due to salt creep. However, the potential for salt damage and fracturing exists. The analyses predict tensile stresses at locations with sharp-edges in the wall geometry, or in the case of cavern 5, in the neck region between the upper and lower lobes of the cavern. The effects do not appear to be large-scale, ...
Date: April 1, 2009
Creator: Ehgartner, Brian L. & Sobolik, Steven Ronald
Partner: UNT Libraries Government Documents Department

Alumina Miniplant Operations: Separation of Aluminum Chloride Liquor from Leach Residue Solids by Classification and Thickening

Description: Report issued by the Bureau of Mines over recovery methods of alumina through leaching of kaolin clay. The materials, equipment, and procedures used are discussed. This report includes tables, and illustrations.
Date: 1983
Creator: Sorensen, Roy T.; Sawyer, Dwight L., Jr. & Turner, Theodore L.
Partner: UNT Libraries Government Documents Department

Experimentation on the Extraction of Uranium from Western Ores by Leaching with Sodium Carbonate and Sodium Bicarbonate

Description: Purpose: "The purpose of the following experiments was to obtain data on the selective extraction of uranium over vanadiur from samples of vanadium ores by leaching with sodium carbonate or sodium bicarbonate solutions, with the object of establishing the time, temperature, and concentration conditions necessary for satisfactory extractions."
Date: December 3, 1943
Creator: Saunders, E. R. & Carosella, M. C.
Partner: UNT Libraries Government Documents Department

The Application of Neutron-Activation Analysis to the Determination of Leach Rates of Simulated Nuclear-Waste Forms

Description: The application of neutron activation analysis to the determination of element release from simulated nuclear waste forms during leaching is described for several different glasses. Potential neutron irradiation effects are discussed, and it is shown, by a series of leach tests on activated and non-activated glass samples, that neutron irradiation has no discernible effect on the release of silicon and cesium during leaching. The radioisotopes best suited for analysis with this method and their associated detection limits are identified, and the method's applicability to waste forms other than glass is discussed.
Date: February 1982
Creator: Bates, J. K.; Jardine, L. J.; Flynn, K. & Steindler, M. J.
Partner: UNT Libraries Government Documents Department